ENHANCED IRRADIATION SELF-CROSS-LINKING AND CO-CROSS-LINKING WITH NITRILE RUBBER OF POLY(VINYL CHLORIDE) WITH PENDENT N,N-DIETHYLDITHIOCARBAMATE GROUPS
Wj. Yang et al., ENHANCED IRRADIATION SELF-CROSS-LINKING AND CO-CROSS-LINKING WITH NITRILE RUBBER OF POLY(VINYL CHLORIDE) WITH PENDENT N,N-DIETHYLDITHIOCARBAMATE GROUPS, European Polymer Journal, 33(5), 1997, pp. 761-765
In order to realize the self-crosslinking of poly(vinyl chloride) (PVC
) and the co-crosslinking of PVC with nitrile rubber (NBR) under UV li
ght irradiation, PVC with pendent N,N-diethyldithiocarbamate groups (P
VC-SR) was prepared through the reaction of PVC with sodium N,N-diethy
ldithiocarbamate in butanone and was then used to enhance the crosslin
king reactions. The effects of UV irradiation time, ambient temperatur
e, PVC-SR functionality and the mixing ratios of PVC-SR/NBR on the deg
ree of gel were investigated and the products were characterized by FT
-IR spectra, UV spectra and DSC. The results showed that PVC-SR and th
e blends of PVC-SR with NBR easily self-crosslinked and co-crosslinked
, respectively, under UV irradiation. However, these reactions did not
happen for either PVC, NBR or the blends of PVC with NBR, i.e. the in
troduction of N,N-diethyldithiocarbamate groups effectively enhanced t
he irradiation crosslinking. The UV spectrum showed that PVC-SR dissoc
iated into macromolecular side-chain sulfur radicals and these radical
s resulted in crosslinking reactions. (C) 1997 Elsevier Science Ltd. A
ll rights reserved.